Pilot and burner control apparatus



Aug. 7, 192s.

F. A. GAUGER ET AL PILOT AND BURNER CONTROL APPARATUS' Filed May 29, 1925 Sheets-Sheet l y gaga@ Aug. 7, 192g 1,680,263

F. A. GAUGER ET AL PILOT AND BURNER CONTROL APPARATUS FiledMayvZQ, 1925 2 Sheets-Sheet 2 Patented Aug. 7, 1928.

UNITED "STATES,

PATENT OFFICE.

FRANKA. GAUGnB`noY w. JoHNsoN,`AND ARTHUR J. NEUsEa, or MILWAUKEE,

` 9 y WIscoNsIN.

.y PILOT AND VBURNER CONTROL APPARATUS. Y

Application le'd Kay ,29,` 1925. Serial No. 33,698.

This invention relates to improvements in pilot and burnercontrol apparatus, and more especially to such apparatus adapted `for use in connection with gas appliances having gas burners therein. The present application and the cci-pending application of Frank A. Gauger, Roy W. Johnson and Arthur J. Neuser,1fled-J'uly 18, 1927 Serial No. 206,-

725, both relate to the same generalsubject The apparatus is especially adapted tor use in connection with gas appliances y1n which the main burner is somewhat enclosed by a casing, housing orvotherwise. In, practically all gas appliances thereis provided such a casing or housing for. thepurpose of conlining the heat.

. By the use of our invention, we-are enabled to use a Bunsenpilot light and thus provide. ai blue smokeless flame. .The apparatus is sc constructed also that the concussion occurring upon the yignition `of the main burner does not extinguish ,the pilot light. r-

Another featureof our invention is the provision of a singlel valve which acts both as a safety valve and also regulates the gas or fuel supply-to the main burner.

Our apparatus is also so constructed that the thermostat forming a part of the apparatus is protected from colddrafts of air such as frequently `may be found in kbasements where gas appliances are installed. Y

Other features and advantages of'our m- '1, Lvention will appear more fully aswe proceed a viewv taken as indicated bythe line 3 lof F 2.

As shown in the drawings, 10 indicates the housing or casing of a gas` appliance such as,

for example, a water heater havingtherein the usual water coil 11.v Below the water coil 1s arranged, in the usualmanner, the main gas burner 12 to which `gas or other suitable fuel is admitted through the pipe 13.V 14 indicates the main gas supply pipe which supplies fuel 'both to the pilot and the main burner.

15` indicates, in general, a member here shown as a box-like casting adapted to house the gas valve and also serving as a lsupport at vits upper end for the pilot tube and ther- Inostat. As shown in Fig. 2, the fuel pipe 'M enters the casting 15 at one side per- `mittlng gas to enterthe chamber 16. From the chamber 16 a'port 17 leads to the end ofkfthe pipe 13 which goes to the burner12.

. It will be seen that gas coming fromthe fuel pipe 14 must pass throughgthe port 17 to reach the burner 12. The port 17 is controlled by a valve 18 providedwith a valve 'stem 19 as shown. A spiral spring 2O operates normally to hold the f valve 18 open;y

We Will'now describe the` apparatus used for controlllng the valve 18 during the ordinary operation of the gas appliance, assuming that there has been noy failure of the pilot light. Opposite to the valve 18.is arranged a slidable. plunger 21 which is urged inwardy, that is, toward the valve 18, by means of the spiral spring 22. The outer end of the plunger21 is provided with an annular groove 23 in which is fitted the y forked, end` 24 of the bell crank "leverl 25 `which is pivoted atV 26. The arm 27 of the bell crank lever has attached at its vouter end .a weightf28 tending to pull the arm 27 down- Ywardly because ofthe force of gravity. Also attached tothe arm 27 is a Wire `or cable 29 leading upwardly to a time control mechis a spiral spring 31 for the purpose of absorbing jars. The time control mechanism f3() is not shown ordescribed in detail as the -same comprisesno, part of the present invention.v For the purpose of understanding the construction and operation of the rest of lthe apparatus, however, we 'may state that this time control apparatus may comprise "clockwork mechanism adapted to be set to anism 30. Interposed in the Wire or cable 29 release the wire 29 ata predetermined time. l It will be seen that, upon the release of the VWire 29, the weight 28 will rock the bell valve 18 will be closed in the event the pilot end of the tube is a plug 36 against which the end ofthe rod 35 rests.

light goes out. In general, suc-h means include a thermostat' kept hot while thepilot light is burning. Upon failure of thepilot light, the thermostat cools and thereby closes th'evalve 18.V 32indicates the Bunsen pilot tube having the flame end 33 inside of the gas supply casing 10 and overthe main burner 12. `Arranged above the Bunsen pilot tube is a tlier-mostat comprising thetube 34 having inside of it the rod 35. In the The tube and rod are made of different metals, having different coeflicients of expansion. For exam-i ple, tube 34 may becopper and the rod 35 some other metal that does not expand so rapidly. Attached to the end 36 of the tube 34 is a cap 37 which lies inside of theV gas appliance casing just above the pilot flamev at the end 3 3'0f pilot 32 so that the burning ofthe pilot willkeep the cap 37 hot. The outer end of the tubel34 as indicated at' 38 isjoine'd to the casting 15.v The rod 35 however, is somewhat longer'and has'its end 39 projecting out through a suitable holein the casting and provided'at its end with a slight depression. 'AttachedtoV the outer side of the casting 15 is a yfulcrum bracket 40 carrying the ,fulcrum 41 against which isVV balanced the lever 42. 43 indicates a nut havinga pair of knife edges 44 engaging the inner side of the lever42. The knife edges- 44 are slightly below the fulcruni 41. The nut43 carries an adjusting'screw 45 having its inner end resting in the depression at the end 39 of the rod 35.` The lower end of the lever 42 is forked as indicated by 46 and embraces the valve stein 19. A. spring 47 urgesthe lower end of the lever 42 inwardly. It will bey seen 'that theoffsetting of the fulcrum l41 and 44 causes movement ofthe lever 42 outwardly (asviewed in Fig. 2) when the endV 39 ofthe rod 35 moves outwardly. Such movement of the"k rod is caused by contraction of thetube 34 upon cooling, and vice versa. The outer end of the valve stem 19 is somewhat reduced in diameter'as indicated by 48 and a washer 49 is held against theshoulder thus formed by means of a spiral spring'50.

In normal operationwitli the pilot light burning the valve 18l remains open unless it is closed by means of the plunger 21. The parts are so proportioned and adjusted that the heat from the pilot flame against the cap 37 keeps the tube 34 sufficiently hot and con# sequently lengthened so that the end 39 of" the rod is :held iii s'ufiicientlysothatthe forked end 46 ofthe lever 42 is held in far enough, as shown in Fig. 2, so that the valve 18 remainso'penl If the pilot light goes out, the cap and tube 34 cool, and the latter contracts. This forces the end 39 of the rod 3`5=outwardly, to theleft, y( as viewedin Fig.2)" thus"swinging the kfork 46 of the lever 42 outwardly against the Washer 49 to move tlie'valve 18 to the left and thus close the same thereby shutting olf all gas to the Imain burner. The spring 50 is stiff enough to'overco'nie resistance of the spring 20`so that as Vlever 42 moves to the left the valve 18 will be closed." i i Means are also provided so that a Bunsen pilot light 'canbe used without danger of' the saine being extinguished from the con-- cussion caused by the ylighting or extinguishing ofthe main burner. V"A Bunsen flame is preferable to the ordinary carbon'flame as it is practically smokeless; and considerably hotter; Heretofore, however, difficulty has been eXperiencedin using asn'iallBunsenV pilot due to the fact that the gas coming through the pilot orifice is of such a small amount that it has practically novelocity In theBunsen `type of burner there is an air inlet adjacent tothe ga'sorifice; Heretofore, when it Was attemptedto use the Bunsen pilot it was found that when the. concussion accompanying the lighting or extinguishing of the main burnertook place, such ka draft of air was carried through the yBunsen tube as to putv out thepilot'light. In our device, we have surrounded the entire Bunsen tube and also the therniostatby the air tube 51 which has its inner end 52 Vlying'inside of the gasappliance housing or casing 10'. I t will be seen that the inner 4end of the lBunsen tube and the vcap 37'of Vthe thermostat project slightly beyond the Lend of thetube 53 indicates the air'inlet in the Bunsen tube 32 and 54 the gas orifice or jetii It willjbe seen that means of this construction air entering 'the inlet 53 comes from the inside of thetubeI 51 which has itsV open end lying inside of the casing 10.' Thus when there is a concussion inthe heater the pressure at the end of the tube"52'is the saine as that in the pilot tube 33. Consequently 'when such concussion occurs, there is no rush 'of air through the pilot tube 32 and consequently lio quently occur in basements and similar places Where gas appliances are often installed.

It is to be noted that by the use of our invention only one valve 18 is provided which acts as a safety valve for the pilot and Ialso serves to regulate 'the gas supply.

It will be seen also that dropping of the weight 28 permits the spring 22 to move the plunger 21 to close the valve 18 and that the forked end 24 of the bell crank lever also operates to movethe plunger 21. cates a gas supply pipe connected to the pipe 14 and adapted to supply gas to the Bunsen 'f pilot light.

While We have shown and described certain embodiments of our invention, it is to .be

understood that it is capable of many modifications. Changes, therefore, in the construction and arrangement may be made Without departing from the spirit and scope of the invention as disclosed in the appended claims, in which it is our intention to claim all novelty inherent in our invention as broadly as possible in view ofthe prior art.

What we claim as new, and desire to secure by Letters Patent, is:

l. In combination with a gas appliance having a casing and main burner therein; a Bunsen burner pilot tube disposed exteriorly of said casing and having its flame end protruding therethrough adj-acent the main burner of the gas appliance; and an air connection between the air inlet of the Bunsen burner tube in rear of the flame and the interior of the casing. y Y

2. In combination with a gas appliance having a main burner therein; a Bunsen burner tube having its flame end lying inside of t-he gas appliance and adjacent the mainburner; and a larger tube surrounding the Bunsen burner tube having the end adjacent the flame end of the Bunsen tube open and lying inside of the gas appliance and the other end closed so as tocause variation of the pressure in the Bunsen tube in rear of t-he flame in accordance with pressure fluctuv ations in the gas appliance.

3. In combination with a gas appliance having a main burner therein; a tube having one end opening into the interior of the gas appliance adjacent the main burner and the other end closed and lying outside the gas appliance; a 'second smaller Bunsen l burner pilot tube lying inside of said first mentioned tube with its flame end adjacent the open end' thereof and near the main 55 indi- Y burner of the gas appliance and its air inlet end lying inside of first mentioned tube near the closed end thereof whereby the pressure in said Bunsen tube in rear of the flame will fluctuate with changes in pressure in the gas appliance.

4. In combination with a gas appliance having a casing and a main burner therein,

a burner pilot tube having its flame end dismixture Within the tube in rear of the flame is maintained substantially equal to the pressure in the casing to prevent the flame from being extinguished.

l5. In combination with a gas appliance 'having a casing and a main burner therein,

a burner pilot tube having its flame end disposed within the casing and in igniting relation to the burner, the outer end of the pilot t-ube having an air inlet leading into the interior thereof, a gas supply member projecting into the tube at the air inlet end of the same whereby a combustible mixture of gas and air is formed in the tube and burns atV the flame end thereof, a large tube surrounding the burner pilot tube and the air inlet thereof and having its end adjacent the flame end of the pilot tube open and in free communication with the interior of the casing, the outer end of the large tube being closed whereby the pressure of the combustible mixture within the pilot tube in rear of the flame is maintained substantially equal to the pressure within the casing to prevent the flame from being extinguished.

6. In combination with a gas appliance having a casing and a main burner therein, a burner pilot tube having a flame burning at an end thereof disposed within the casing and in igniting relation to the burner, and means coacting with the casing and with the pilot tube in rear of the flame whereby the pressure in the tube is maintained substantially equal to the pressure in the casing.

Witness our hands this 20th day of May,

FRANK A. GAUGER. ROY W. JOHNSON. ARTHUR J. NEU SER. 

